A negatively charged particle experiences downward force of 0.040N due to a magnetic field strength of 0.50T. If the particles of charge is -1.6nC, how fast was it moving when it entered the magnetic field? What I did was go Fm=qvb. So 0.04M/(1.6E-9C x 0.50T) = 50 000m/s but the answer is 50 000 000 m/s???? Is the textbook wrong? Thanks.